Hello! Thanks for your very useful tool! I have not found a lot of monorepo tools for smaller organizations (i.e. not Facebook and Google sized and complexity), especially implemented in Go or with a focus on Go, so you might consider adding a Github topic of monorepo to make it easier to discover this project.
At the same time, there are a few other, somewhat similar or related tools that might be useful to mention in your Readme, or perhaps to draw inspiration from.